Figure 3From: Changes in blood hemoglobin and blood gases PaO2 and PaCO2 in severe COPD overa three-year telemonitored program of long-term oxygen treatmentTime course of SaO 2 values in the whole cohort and in each subgroup: t test between t 0 and t 1 . Hb, hemoglobin; SaO2, oxyhemoglobin saturation.Back to article page